The comet proposed as a trigger for the Younger Dryas would have required approximately one million times the energy of the object that created Arizona's Meteor Crater, which is three-quarters of a mile wide.
Notes on verification
Meteor Crater's three-quarter-mile diameter is well established by multiple independent sources. The 'million times the energy' figure traces largely to a single scientist's (Boslough) order-of-magnitude comparison, repeated across outlets rather than independently recomputed, and the underlying Younger Dryas impact hypothesis itself remains scientifically contested.
Sources
- Did a Comet Really Kill the Mammoths 12,900 Years Ago? (nationalgeographic.com)
- https://www.nbcnews.com/news/all/dont-blame-comet-clovis-culture-demise-scientists-say-flna1C8644296 (nbcnews.com)
- https://meteorcrater.com/attraction/az-meteor-crater/ (meteorcrater.com)
- https://liberalarts.tamu.edu/csfa/wp-content/uploads/sites/14/2021/10/MT-29-3-color.pdf (liberalarts.tamu.edu)